PRB: RDO Run-time Error '40060': Incorrect Type for Parameter

• Microsoft Visual Basic Enterprise Edition for Windows, version 5.0

SYMPTOMS

When assigning the value of a field from one Resultset to another (such as, rs2!FieldX = rs1!FieldY), you may get the following error:

   Run-time error '40060'
   Incorrect type for parameter

CAUSE

FieldY has a NULL value.

RESOLUTION

To resolve this problem, do one of the following:

• Use the following assignment expression:

        rs2!FieldX = rs1!FieldY.Value
  

• Assign the value of the field to a Variant variable as an intermediate step:

        MyVariant = rs1!FieldY
        rs2!FieldX = MyVariant
  

STATUS

Microsoft is researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Steps to Reproduce Behavior

1. Use ISQL/W or another tool to create a table using the following SQL statement:

         CREATE TABLE dbo.TestNull (
           ID int NOT NULL ,
           F1 varchar (10) NULL ,
           CONSTRAINT PK_TestAddNew_1__15 PRIMARY KEY  CLUSTERED
             (
             ID
             )
         )
   
   

2. Add a record, leaving F1 with a NULL value. You may do this in ISQL/W or VISDATA in Visual Basic.

3. In Visual Basic 5.0, create a new project.

4. Reference Microsoft Remote Data Objects 2.0.

5. Add a command button (Command1) and the following code:

         Private Sub Command1_Click()
         Dim cn As rdoConnection, rs1 As rdoResultset, rs2 As rdoResultset
           rdoEngine.rdoDefaultCursorDriver = rdUseServer
           Set cn = rdoEngine(0).OpenConnection("", rdDriverNoPrompt, False, _
             "Driver={SQL Server};Server=moonbase;uid=sa;pwd=;database=pubs")
           Set rs1 = cn.OpenResultset("SELECT * FROM TestNull", _
             rdOpenKeyset, rdConcurValues, rdExecDirect)
           rs1.MoveLast
           Set rs2 = cn.OpenResultset("SELECT * FROM TestNull", _
             rdOpenKeyset, rdConcurValues, rdExecDirect)
           rs2.Edit
           rs2!F1 = rs1!F1
           rs2.Update
           rs1.Close
           rs2.Close
           cn.Close
         End Sub
   
   

6. Run the project and click the command button and the error message will appear.

7. Change the line:

          rs2!F1 = rs1!F1
   

   to:

          rs2!F1 = rs1!F1.Value
   

8. Run the project again, and the error will not appear.

Keywords          : VBKBRDOResultSet
Version           : WINNT:5.0 WIN95:5.0
Platform          : Win95 winnt
Issue type        : kbprb